During database application development, we often need to deal with complicated SQL-style computations. The transposition of rows and columns is one of them. Oracle uses pivot function to realize thi More...

It is difficult for MongoDB to realize the operation of cross summarizing. It is also quite complicated to realize it using high-level languages, like Java, after the desired data is retrieved out. I More...

During database application development, we often need to handle complicated SQL-style computations. One of them is the ungrouping, that is, the opposite process of grouping and summarizing which req More...

MongoDB doesn’t support join. The unity JDBC recommended by its official website can perform join operation after retrieving data out, but charges a fee for the service. Other free JDBC driver More...

MongoDB uses unicode, instead of the coding for a certain local language, to sort data in this language (i.e. Chinese). Together with esProc, MongoDB can realize sorting in local language convenientl More...

esProc can help Java deal with various computations in processing structured texts. But in the case of non-single row records, it is necessary to preprocess the data before esProc can perform computa More...

The join statements of the database can be used conveniently to perform the operation of alignment join. But sometimes the data is stored in the text files, and to compute it in Java alone we need to More...

While importing the structured text files into the database using Java alone, we need to combine the SQL statements together manually, and to deal with various troublesome situations as well, like if More...